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genai-toolbox/docs/en/samples/pre_post_processing/python.md
Twisha Bansal 1664a69dfd docs: add pre/post processing docs for langchain python (#2378)
## Description

Trigger has been tested corresponding to local changes. Latest
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Note: After merging, update python pre and post processing sample
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Python docs 1 How to add pre- and post- processing to your Agents using Python.

Prerequisites

This tutorial assumes that you have set up Toolbox with a basic agent as described in the local quickstart.

This guide demonstrates how to implement these patterns in your Toolbox applications.

Implementation

{{< tabpane persist=header >}} {{% tab header="ADK" text=true %}} Coming soon. {{% /tab %}} {{% tab header="Langchain" text=true %}} The following example demonstrates how to use ToolboxClient with LangChain's middleware to implement pre- and post- processing for tool calls.

{{< include "python/langchain/agent.py" >}}

You can also add model-level (wrap_model) and agent-level (before_agent, after_agent) hooks to intercept messages at different stages of the execution loop. See the LangChain Middleware documentation for details on these additional hook types. {{% /tab %}} {{< /tabpane >}}

Results

The output should look similar to the following. Note that exact responses may vary due to the non-deterministic nature of LLMs and differences between orchestration frameworks.

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